Atlantoaxial instability was not only frequent in high cervical OPLL but was also identified in low cervical OPLL.
Atlantoaxial and subaxial spinal fixation essentially formed the basis of surgical treatment in these cases.
The exact role of atlantoaxial instability in the initiation and progression of degenerative spondylotic changes in the subaxial spine remains to be identified.
However, it is crucial to evaluate the status of the atlantoaxial joint especially in high cervical spondylosis and in cases where the neurological deficits are significant and disproportionate to the extent of spinal changes observed on imaging.
The author is convinced that atlantoaxial instability is significantly common in cases with multiple levels spinal degeneration and is probably an underestimated and undertreated entity.
Failure to treat atlantoaxial instability could be the cause of failure of surgical treatment.Report of early results with a preliminary experience in 14 patients. Fujiyoshi T, Yamazaki M, Okawa A, Kawabe J, Hayashi K, Endo T, et al. Facet distraction spacers for treatment of degenerative disease of the spine: Rationale and an alternative hypothesis of spinal degeneration. Static versus dynamic factors for the development of myelopathy in patients with cervical ossification of the posterior longitudinal ligament. As multiple level bone removal has been identified to result in instability in the long-run, a host of stabilization procedures have been discussed.In general, the exact pathogenesis of OPLL has only been speculated as no definite or conclusive incriminating factor has been identified on the most instances.Over several decades, the pathogenesis of cervical spondylosis has been convincingly related to primary disc degeneration, disc space reduction, and subsequent relentlessly progressive pathological processes such as osteophyte formation, ligamentum flavum hypertrophy, facetal retrolisthesis, and similar such events that eventually result in spinal and neural canal stenosis and related neurological symptoms and deficits.Decompression of the neural structures by removal of the offending bone and soft-tissue elements by anterior cervical route by single or multiple level corpectomy or by posterior route by laminectomy or foraminotomy or by laminoplasty is the accepted and widely practiced mode of surgical treatment. J Craniovert Jun Spine [serial online] 2018 [cited 2019 Sep 7];9:1-2. 2018/9/1/1/230612 There has been an ongoing discussion for decades about the causal relationships between ossification of posterior longitudinal ligament (OPLL) and cervical spondylosis. Ossification of posterior longitudinal ligament and cervical spondylosis: Same cause - Same treatment.It was realized that multiple segmental spinal instability was also the nodal and primary pathogenetic issue in cases with OPLL.Atlantoaxial instability was relatively more often associated than in cases with only cervical spondylosis.